One vertex per element, one color per generator, with an edge from x to x·s.
(1,2,4,6)(3,5,7,8)(9,10)(11,15)(12,14)(13,16)(17,18,20,22)(19,21,23,24)(25,26,30,27)(28,31,35,33)(29,34,37,32)(36,39,40,38)(9,11)(10,15)(12,13)(14,16)(17,19,20,23)(18,21,22,24)(26,27)(28,35)(32,34)(36,40)(10,12)(11,16)(17,19)(18,21)(20,23)(22,24)(25,27,30,26)(28,31,35,33)(29,32,37,34)(36,39,40,38)(1,2)(3,5)(4,6)(7,8)(9,12,14,10)(11,13,16,15)(25,28)(26,31)(27,33)(29,36)(30,35)(32,38)(34,39)(37,40)(1,3,4,7)(2,5,6,8)(9,13)(10,11)(12,16)(14,15)(17,18)(19,21)(20,22)(23,24)(25,29,30,37)(26,32,27,34)(28,36,35,40)(31,38,33,39)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.